[show abstract][hide abstract] ABSTRACT: Teratomas are very rare intracranial tumors and cytogenetic information on this group remains rare. We report a case of a mature teratoma with abnormal +21 trisomy in tumor karyotype ocurring in a non-Down syndrome (DS) infant. Additionally, the evidence for the contribution of chromosome 21 trisomy in this neoplasia are briefly reviewed. The 6-month-old male baby presented with a posterior fossa tumor. Histological evaluation of tumor specimen showed a mature teratoma composed of fully differentiated ectodermal, mesodermal and endodermal components. Although somatic karyotyping of the index case was normal, composite tumor karyotype depicted 47, XY, +21/46,XY. Besides previous reports of children with DS and intracranial teratomas, this is the first report to describe the occurrence of an isolated chromosome 21 trisomy within the tumor of a non-DS child. The participation of chromosome 21 in this rare pediatric tumor, either somatic or restricted to tumor specimen, may deserve special interest and further investigation.
[show abstract][hide abstract] ABSTRACT: Mowat-Wilson syndrome (MWS) is a rare genetic condition where variable and multiple congenital anomalies including Hirschsprung's disease, intellectual disability, and prominent facial features are present. At molecular level, MWS is characterized by many different described mutations in the zinc finger E-box protein 2 (ZEB2) gene, ultimately leading to loss of gene function. This report is the first to describe the association of MWS with two different asynchronous malignant brain tumors (medulloblastoma and glioblastoma) occurring in a child.
Child s Nervous System 10/2013; · 1.24 Impact Factor
[show abstract][hide abstract] ABSTRACT: PURPOSE: John Cunningham (JC) viral DNA sequence has seldom been reported in patients with brain tumors such as high grade gliomas and medulloblastomas, pointing to a role in the etiopathogenesis of such tumors. RESULTS: We present a unique clinical case of an HIV-positive pediatric patient with multifocal leukoencephalopathy and confirmed JC virus (JCV) infection that developed a giant-cell glioblastoma. CONCLUSIONS: Experimental data with infected primates has previously hypothesized an association of human giant-cell glioblastoma with JCV or progressive multifocal leukoencephalopathy, though such association has not been documented in the literature for humans. Future studies with larger cohorts and molecular pathological analyses are still needed to corroborate the role of the widely spread human neurotropic virus in early transformation and in the development of brain tumors with different histology in the setting of HIV-related severe immunosuppression.
Child s Nervous System 05/2013; · 1.24 Impact Factor
[show abstract][hide abstract] ABSTRACT: Abstract Osteosarcoma (OS) is the most common primary malignant bone tumor. Despite advances in neoadjuvant multi-agent chemotherapy, the outcome of patients has not significantly improved in the last decades, making the search for more effective therapeutic agents imperative. In the present study, we explored the possibility of using activator protein-1 inhibition by 3-[(dodecylthiocarbonyl)methyl]-glutarimide (DTCM-g) as a new therapeutic strategy in two OS cell lines, HOS and MG-63. Our results showed that low concentrations (2.5, 5, 10, and 20 μg/mL) of the drug significantly decreased cell proliferation and clonogenic capacity, albeit it did not significantly induce cell death. DTCM-g also decreased cell invasiveness, and inhibited PDPN, MMP-2, TIMP1, and TIMP2 expressions. Moreover, our results showed that DTCM-g synergized with ionizing radiation in both cell lines while chemosensitized MG-63 cells to doxorubicin treatment. Even though additional laboratorial and preclinical tests are still needed to support our data, we demonstrate that DTCM-g inhibits growth in OS cells, increases the cytotoxicity of other commonly used agents, and may possess antimetastatic activity.
Cancer Biotherapy & Radiopharmaceuticals 01/2013; · 1.44 Impact Factor
[show abstract][hide abstract] ABSTRACT: Chromosomal heterogeneity is a hallmark of most tumors and it can drive critical events as growth advantages, survival advantages, progression and karyotypic evolution. Medulloblastoma (MB) is the most common malignant central nervous system tumor in children. This work attempted to investigate chromosomal heterogeneity and instability profiles of two MB pediatric cell lines and their relationship with cell phenotype. We performed GTG-banding and cytokinesis-block micronucleus cytome assays, as well as morphological characterization, cell population doubling time, colony-forming efficiency, and chemo-sensitivity assays in two pediatric MB cell lines (UW402 and UW473). Both MB cells showed a high chromosomal heterogeneity. UW473 cells showed ~2 fold higher both clonal- and non-clonal chromosomal alterations than UW402 cells. Besides, UW473 showed two clonal-groups well-differentiated by ploidy level (<2n> and <4n>) and also presented a significantly higher number of chromosomal instability biomarkers. These results were associated with high morphological heterogeneity and survival advantages for UW473 and proliferation advantages for UW402 cells. Moreover, UW473 was significantly more sensitive to methotrexate, temozolomide and cisplatin while UW402 cells were more sensitive to doxorubicin. These data suggest that distinct different degrees of karyotypic heterogeneity and instability may affect neoplasic phenotype of MB cells. These findings bring new insights into cell and tumor biology.
[show abstract][hide abstract] ABSTRACT: Despite advances in neurosurgery and aggressive treatment with temozolomide (TMZ) and radiation, the overall survival of patients with glioblastoma (GBM) remains poor. Vast evidence has indicated that the nuclear factor NF- κ B is constitutively activated in cancer cells, playing key roles in growth and survival. Recently, Dehydroxymethylepoxyquinomicin (DHMEQ) has shown to be a selective NF- κ B inhibitor with antiproliferative properties in GBM. In the present study, the ability of DHMEQ to surmount tumor's invasive nature and therapy resistance were further explored. Corroborating results showed that DHMEQ impaired cell growth in dose- and time-dependent manners with G2/M arrest when compared with control. Clonogenicity was also significantly diminished with increased apoptosis, though necrotic cell death was also observed at comparable levels. Notably, migration and invasion were inhibited accordingly with lowered expression of invasion-related genes. Moreover, concurrent combination with TMZ synergistically inhibited cell growth in all cell lines, as determined by proliferation and caspase-3 activation assays, though in those that express O(6)-methylguanine-DNA methyltransferase, the synergistic effects were schedule dependent. Pretreatment with DHMEQ equally sensitized cells to ionizing radiation. Taken together, our results strengthen the potential usefulness of DHMEQ in future therapeutic strategies for tumors that do not respond to conventional approaches.
Chemotherapy research and practice. 01/2013; 2013:593020.
[show abstract][hide abstract] ABSTRACT: Ionizing radiation is the most recognized risk factor for meningioma in pediatric long-term cancer survivors. Information in this rare setting is exceptional. We report the clinical and cytogenetic findings in a radiation-induced atypical meningioma following treatment for desmoplastic medulloblastoma in a child. This is the second study to describe the cytogenetic aspects on radiation-induced meningiomas in children. Chromosome banding analysis revealed a 46, XX, t(1;3)(p22;q12), del(1)(p?)/46, XX. Loss of chromosome 1p as a consequence of irradiation has been proposed to be more important in the development of secondary meningiomas in adults. Deletions in the short arm of chromosome 1 also appear to be a shared feature in both pediatric cases so far analyzed.
Journal of Neuro-Oncology 10/2012; · 3.12 Impact Factor
[show abstract][hide abstract] ABSTRACT: The goal of this study was to determine the epidemiology, clinical presentation, associated factors, pathological features, and treatment outcome of pediatric meningiomas in a single-center institution.
Clinical data of 15 patients under 18 years of age operated on for meningiomas from January 1994 to December 2010 were reviewed.
The study group included nine males and six females (mean age of 13 years at surgery). The most common symptoms at presentation were headaches in 6 out of 15 (40 %), raised intracranial pressure in 3 out of 15 (20 %), and seizures in 3 out of 15 (20 %). Sole operated tumors were found in 12 out of 15 (80 %), whose location is as follows: parasagittal in 4 out of 12 (33.3 %), 2 in the convexity (16.6 %), 2 at the skull base (16.6 %), and 4 in other sites (33.3 %). Six children presented with radiation-induced (RT) meningiomas and five had evidence of neurofibromatosis type 2 (NF2). Three patients had multiple meningiomas (all of them had NF2). Simpson's grade I excision was achieved in 12 out of 15 (80 %). On histopathology, 11 out of 15 (73.3 %) were grade I and 4 out of 15 (26.6 %) were grade II (all of them atypical). Five tumors (33.3 %) recurred, four of which had RT or NF2. During the mean follow-up period of 5 years, 12 out of 15 (80 %) had a good outcome (GOS = 5).
Childhood meningiomas are uncommon lesions with a slight male predominance. Absence of large series with long follow-up precludes any definite conclusions on the clinical course and outcome of these tumors. Associated factors (such as RT and NF2), location, and extent of excision appear to be more important than histopathological grade in predicting outcome.
Child s Nervous System 06/2012; 28(11):1887-96. · 1.24 Impact Factor
[show abstract][hide abstract] ABSTRACT: Melanoma is one of the most treatment-resistant malignancies and regardless of new therapeutic tactics the outcome remains dismal. Polo-like kinase 1 (PLK1) has been shown to be over-expressed in a variety of tumors, becoming an attractive target for cancer management. In the present study we tested the in vitro antitumor activities of BI 2536, a selective inhibitor of PLK1, against two melanoma cell lines. Our results showed that nanomolar concentrations (10-150 nmol/L) of the drug significantly decreased cell proliferation and clonogenicity, promoting cell cycle arrest in G2/M. Targeting the cell cycle offers an attractive potential cancer-treatment option. Herein we show that PLK1 inhibition may be a feasible approach for the impairment of tumor progression and dissemination. This in vitro profile of melanoma cell growth inhibition by PLK1 modulation may be an interesting model to be tested in association with first-line antineoplasic agents in melanomas.
Journal of drugs in dermatology: JDD 05/2012; 11(5):587-92. · 1.16 Impact Factor
[show abstract][hide abstract] ABSTRACT: Bladder cancer is a common malignancy worldwide. Despite the increased use of cisplatin-based combination therapy, the outcomes for patients with advanced disease remain poor. Recently, altered activation of the PI3K/ Akt/mTOR pathway has been associated with reduced patient survival and advanced stage of bladder cancer, making its upstream or downstream components attractive targets for therapeutic intervention. In the present study, we showed that treatment with DTCM-glutaramide, a piperidine that targets PDK1, results in reduced proliferation, diminished cell migration and G1 arrest in 5637 and T24 bladder carcinoma cells. Conversely, no apoptosis, necrosis or autophagy were detected after treatment, suggesting that reduced cell numbers in vitro are a result of diminished proliferation rather than cell death. Furthermore previous exposure to 10 μg/ml DTCM- glutarimide sensitized both cell lines to ionizing radiation. Although more studies are needed to corroborate our findings, our results indicate that PDK1 may be useful as a therapeutic target to prevent progression and abnormal tissue dissemination of urothelial carcinomas.
Asian Pacific journal of cancer prevention: APJCP 01/2012; 13(5):1957-62. · 1.27 Impact Factor
[show abstract][hide abstract] ABSTRACT: Cancer-prone genetic disorders are responsible for brain tumors in a considerable proportion of children. Additionally, rare genetic syndromes associated to cancer development may potentially disclose genetic mechanisms related to oncogenesis.
We describe two pediatric patients with encephalocraniocutaneous lipomatosis (ECCL), a very rare genetic syndrome with around 60 reported cases, which developed low-grade astrocytoma at 3 and 12 years of age.
Patients with ECCL seem to be at risk of benign forms of osseous tumors such as ossifying fibromas, odontomas, and osteomas.
The association between brain tumor and ECCL was previously reported only once, in a pediatric case of a mixed neuronal-glial histology. Whether ECCL may be a genetic condition of predisposing brain tumor in children strongly needs to be addressed.
Child s Nervous System 01/2012; 28(1):19-22. · 1.24 Impact Factor
[show abstract][hide abstract] ABSTRACT: Osteochondroma is a cartilage capped benign tumor developing mainly at the juxta-epiphyseal region of long bones. The rate of malignant transformation, mainly into chondrosarcoma, is estimated to be less than 1-3%. Transformation into osteosarcoma is very rare and has been reported only thirteen times. There is little information on treatment and outcome. We report the case of a secondary osteosarcoma arising in the left tibia of a 23-year-old male, 10 years after the initial diagnosis of osteochondroma and after two partial resections. Malignant transformation occurred at the stalk and not at the cartilage cap, as would normally be expected. Chromosome banding analysis revealed the karyotype: 46,XY, t(3;13)(q21;q34) /46,XY . Records from additional cases will help determine the parameters that define these rare secondary bone lesions.
[show abstract][hide abstract] ABSTRACT: Cavernous hemangioma (CH) is a sporadic vascular malformation occurring either as an autosomal dominant condition or as a well-known complication of radiation exposure. Medulloblastoma is a primitive neuroectodermal tumor common in children and currently treated with surgical resection, chemotherapy, and radiotherapy. Neurofibromatosis is the most common single-gene disorder of the central nervous system. Posterior fossa malignant tumors in the context of neurofibromatosis type I (NF1) are very infrequent. This is the first documented case of an unusual metachronous occurrence of non-radiation-induced CH and medulloblastoma in a child with NF1 phenotype. We report the case of a 13-month-old boy with café-au-lait skin lesions associated with NF1-like phenotype who underwent surgical resection of a single CH in the temporal lobe due to recurrent seizures. Four years later he presented with signs of raised intracranial pressure associated with a posterior fossa tumor and hydrocephalus, thus requiring gross total resection of the lesion. Histological analysis revealed a medulloblastoma. After being treated with radiotherapy and chemotherapy, he achieved total remission. Six years later a massive recurrence of the tumor was observed and the child eventually died. The interest in this case lies in the rarity of NF1-like phenotype associated with a non-radiation-induced brain CH and medulloblastoma in a child.
Journal of Pediatric Neurosciences 01/2012; 7(1):43-6.
[show abstract][hide abstract] ABSTRACT: We analyzed cerebrospinal fluid (CSF) samples from 65 consecutive children with acute lymphoblastic leukemia (ALL) treated according to two different treatment protocols (GBTLI-ALL-93 and -99) with no puncture accident for minimal residual disease (MRD) in the central nervous system (CNS). Minimal residual disease was detected by polymerase chain reaction (PCR) with homo/heteroduplex analysis using consensus primers to IgH and TCR genes. MRD in the CSF at diagnosis was detected by PCR in 46.8% of children with no puncture accident or morphological involvement. In patients treated with GBTLI-ALL-93 a significantly lower 5-year event-free survival (EFS) was demonstrated for those with CSF involvement, in univariate (p = 0.01) and multivariate (p = 0.04) analysis. This observation was not true for patients treated with the more intensive protocol GBTLI-ALL-99 (p = 0.81). These findings suggest that MRD detection in the CSF is a common event in children with ALL. Treatment intensification provided by the GBTLI-ALL-99 apparently overcomes the detrimental effect of CNS minimal residual disease at diagnosis.